In the field of construction it is frequently necessary to install junction boxes for electrical outlets/light switches/power points and the like. Such junction boxes are frequently located within a wall and may be attached to a wall stud or to the rear surface of the finishing panel. In such construction where the wall is to be finished with a sheeting material such as gypsum board, it is necessary to cut a hole in the gypsum board so as that the interior of the junction box may be accessed so as to install light switches/power points and the like therein thereafter the junction box may be covered with a cover plate as are commonly known.
Present difficulties exist in determining the location of junction boxes and the like behind a sheet of gypsum board also in determining the correct entry point for the cutting tool. These difficulties are typically presented during construction when the gypsum board is installed over the top of the junction boxes and the like. Inaccurate measuring and marking of the junction boxes can result in the holes being cut too big or in the wrong position and not corresponding to the junction box location resulting in the loss of time and money.
Previous attempts to solve these difficulties have located a magnet within the junction box and have detected that magnet on the exterior surface of the wall. Such attempts however have not taken into account the affects of gravity and friction on the magnets causing inaccurate marking, an example of this would be as the thickness of the drywall increases the less accurate they would become. Examples of such may be shown in U.S. Pat. Nos. 7,367,131 Horids and 4,384,396 Smolik. Previous attempts also have limitations in respect to the shape being cut relates to the template that is being used if you required numerous shapes and sizes as in various different outlets you would require numerous different templates, the present invention requires no templates once an entry point has been marked a cutting tool is entered at that point piercing through the wall covering then the junction box itself what ever the size or shape is used to guide the cutting tool.
Conventional methods of locating the necessary hole would be to measure the location of the junction box on the wall and then transfer the said measurement onto the gypsum board giving the corresponding hole location, another method would be to use a drywall square which again requires taking and transferring measurements and allowing for human error.